66169969 has 2 divisors, whose sum is σ = 66169970. Its totient is φ = 66169968.

The previous prime is 66169931. The next prime is 66169973. The reversal of 66169969 is 96996166.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 56806369 + 9363600 = 7537^2 + 3060^2 .

It is a cyclic number.

It is not a de Polignac number, because 66169969 - 2¹⁹ = 65645681 is a prime.

It is a super-2 number, since 2×66169969² = 8756929594921922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66169979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33084984 + 33084985.

It is an arithmetic number, because the mean of its divisors is an integer number (33084985).

Almost surely, 2^66169969 is an apocalyptic number.

It is an amenable number.

66169969 is a deficient number, since it is larger than the sum of its proper divisors (1).

66169969 is an equidigital number, since it uses as much as digits as its factorization.

66169969 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 944784, while the sum is 52.

The square root of 66169969 is about 8134.4925471722. The cubic root of 66169969 is about 404.4706165696.

The spelling of 66169969 in words is "sixty-six million, one hundred sixty-nine thousand, nine hundred sixty-nine".